A Waltham-based company that makes traditional Icelandic skyr — a dairy product akin to yogurt — has quietly raised funding from executives and investors at Living Proof, a hair-care company co-owned by actress Jennifer Aniston.

Not much is known about the secretive company called Icelandic Provisions, which raised $11 million in equity funding, according to a Monday regulatory filing.

The company doesn’t appear to have a website yet, but the filing suggests its investors are executives of…